第4题: [单项选择]亚慢性毒性试验如何选择高剂量组剂量() A. 1/20~1/5LD50 B. 1/5~1/2LD50 C. 1/50~1/10LD50 D. 1/30~1/3LD50 E. 1/100~1/50LD50 参考答案:A
第5题:[单项选择]<BR><DIV><TABLEcellSpacing=0cellPadding=0width="100%"border=0><TBODY><TR><TDvAlign=topwidth="100%"></TD></TR></TBODY></TABLE></DIV><br/>参考答案:A 答案解析:[听力原文]
The elevator is broken again.
(A) We’ll have to take the stairs.
(B) He hasn’t spoken ye